JP2012081681A - Screen printing machine and screen printing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a screen printing machine and screen printing method, which can prevent the occurrence of a printing failure due to unequal supply of paste on a mask.SOLUTION: In each of forward and backward motions of a syringe 16 in a reciprocating region R, when the syringe 16 reaches one end side of a paste supply region Q (air pressure supply start position Q1 at a forward path side and air pressure supply start position Q3 at a backward path side), the screen printing machine starts supplying the air pressure to the syringe 16 and stops supplying the air pressure to the syringe 16 before the syringe 16 reaches the other end side of the paste supply region Q (air pressure supply start position Q2 at a forward path side and air pressure supply start position Q4 at a backward path side).

Description

  The present invention relates to a screen printing machine and a screen printing method for transferring a paste to an electrode on a substrate through an opening of a mask.

  A screen printing machine that prints a paste such as a solder paste on a substrate has a substrate having a plurality of openings according to the arrangement of electrodes on the substrate, and the substrate is lifted while the substrate is clamped by a pair of clamp members. The substrate holding and moving means for bringing the upper surface of the substrate into contact with the lower surface of the mask, the squeegee base moved in the horizontal plane above the mask, extending in the horizontal plane perpendicular to the moving direction of the squeegee base, and lifted and lowered below the squeegee base A syringe that discharges paste by receiving a supply of squeegee and air pressure is provided. After the substrate and the mask are brought into contact with each other by the substrate holding and moving means so that the electrode of the substrate and the opening of the mask are matched, Move the squeegee base in the horizontal plane by bringing the lowered squeegee into contact with the mask supplied with the paste. You have me. As a result, the squeegee slides on the mask and the paste is scraped by the squeegee, so that the paste is filled in the opening of the mask and transferred to the electrode.

  In such a screen printing machine, the syringe supplies air pressure to the syringe while moving the syringe in the extending direction of the squeegee to discharge the paste from the syringe, and the paste is automatically supplied to the paste supply area set on the mask. What was made is known (for example, patent document 1).

JP-A-4-107145

  However, in the above conventional device, even if the supply of air pressure to the syringe is stopped when the movement of the syringe is terminated, the discharge of the paste from the syringe does not end immediately, and the inside of the syringe that has become pressurized due to the supply of air pressure. Since the paste continues to come out of the syringe until the pressure of the air pressure returns to the low pressure due to the stop of the air pressure supply, the amount of paste near the end point of the movement of the syringe locally increases. Then, the distribution of the amount of paste in the paste supply area becomes non-uniform as a whole, and when the squeegee is slid on the mask after that, the filling state of the paste into the opening of the mask varies as a whole mask. There has been a problem that printing defects are likely to occur.

  Therefore, an object of the present invention is to provide a screen printing machine and a screen printing method capable of suppressing the occurrence of printing defects due to non-uniform supply of paste on a mask.

  The screen printing machine according to claim 1, wherein the substrate is lifted in a state in which the substrate is clamped by a pair of clamp members, and a mask having a plurality of openings according to the arrangement of the electrodes on the substrate, A substrate holding and moving means for bringing the upper surface of the substrate into contact with the lower surface of the mask so that the opening of the mask matches, a squeegee base moved in the horizontal plane above the mask, and a horizontal plane perpendicular to the moving direction of the squeegee base The squeegee extends inward and is moved up and down below the squeegee base, and is movably provided in a reciprocating movement region set to include both ends of the substrate squeegee extending direction in contact with the mask by the substrate holding and moving means. A syringe that receives the supply of air pressure and discharges the paste, and supplies the air pressure to the syringe while reciprocating the syringe in the reciprocating movement region. In each of the forward path and the return path of the reciprocating movement area, the syringe operation control means for supplying the paste to the paste supply area set on the mask, the squeegee is lowered with respect to the squeegee base, and the paste is supplied by the syringe Squeegee lowering means for bringing the squeegee into contact with the mask, and squeegee base moving means for moving the squeegee base in the horizontal plane while the squeegee is in contact with the mask and sliding the squeegee on the mask. The syringe operation control means starts supplying air pressure to the syringe when the syringe reaches one end side of the paste supply area in each of the forward path and the return path of the movement in the reciprocating movement area of the syringe. The air pressure supply to the syringe is stopped before reaching the other end side.

  The screen printing machine according to claim 2 is the screen printing machine according to claim 1, wherein the syringe operation control means starts the supply of air pressure to the syringe from the start of supply of air pressure to the syringe. Determine based on the elapsed time.

  The screen printing method according to claim 3, wherein the substrate is lifted in a state where the substrate is clamped by a pair of clamp members, and a mask having a plurality of openings according to the arrangement of the electrodes on the substrate, A substrate holding and moving means for bringing the upper surface of the substrate into contact with the lower surface of the mask so that the opening of the mask matches, a squeegee base moved in the horizontal plane above the mask, and a horizontal plane perpendicular to the moving direction of the squeegee base The squeegee extends inward and is moved up and down below the squeegee base, and is movably provided in a reciprocating movement region set to include both ends of the substrate squeegee extending direction in contact with the mask by the substrate holding and moving means. , A screen printing method using a screen printing machine equipped with a syringe that receives a supply of air pressure and discharges a paste, wherein the syringe is moved back and forth. Supplying air pressure to the syringe while reciprocating in the area, supplying the paste to the paste supply area set on the mask in each of the forward path and the return path of the reciprocating area, and a squeegee to the squeegee base The step of lowering and bringing the squeegee into contact with the mask to which the paste is supplied by the syringe, and moving the squeegee base in the horizontal plane while the squeegee is in contact with the mask and sliding the squeegee on the mask When the syringe reaches the one end side of the paste supply area in each of the forward path and the return path of the movement in the reciprocating movement area of the syringe during the process of supplying the paste to the paste supply area with the syringe Start supplying air pressure to the syringe and before the syringe reaches the other end of the paste supply area To stop the supply of air pressure to the syringe.

  The screen printing method according to claim 4 is the screen printing method according to claim 3, wherein the timing of stopping the supply of air pressure to the syringe at the time of executing the step of supplying the paste to the paste supply region by the syringe is set. It is determined based on the elapsed time from the start of supply of air pressure to the syringe.

  In the present invention, supply of air pressure to the syringe is started when the syringe reaches one end side of the paste supply area in each of the forward path and the return path of the movement of the syringe in the reciprocating movement area. The supply of air pressure to the syringe is stopped before reaching the end side, and the paste discharged from the syringe is supplied from the one end side to the point where the supply of air pressure is stopped in the paste supply region. In the portion between the point where the supply of air pressure is stopped and the other end side, the pressure in the syringe, which has been increased due to the supply of air pressure, returns to the low pressure (atmospheric pressure level) due to the stop of air supply In the meantime, the paste is supplied as long as it continues to come out of the syringe. For this reason, after the supply of air pressure to the syringe is stopped, there is no inconvenience that the paste that continues to be discharged from the syringe is intensively supplied to a part of the paste supply region. Since the paste is supplied for each of the forward and backward movements of the reciprocating movement area of the syringe, the paste in the paste supply area is supplied by the supply during the forward movement of the syringe and during the backward movement of the syringe. Due to the supply, it is easy to make uniform as a whole, and it is possible to suppress the occurrence of printing defects due to the non-uniform supply of paste on the mask.

The top view of the screen printer in one embodiment of the present invention The front view of the screen printer in one embodiment of the present invention The side view of the screen printer in one embodiment of the present invention The top view of the mask installed in the mask holder with which the screen printing machine in one embodiment of this invention is equipped, and the mask holder The perspective view of the syringe with which the screen printing machine in one embodiment of this invention is provided The side view of the squeegee and syringe with which the screen printer in one embodiment of this invention is provided. The partial front view of the screen printer in one embodiment of this invention The block diagram which shows the control system of the screen printer in one embodiment of this invention (A) perspective view (b) side view of rear squeegee provided in screen printing machine according to one embodiment of the present invention The top view of the mask holder and mask which show an example of the supply state of the paste of the screen printer in one embodiment of this invention (A) (b) (c) The figure which shows distribution of the paste supplied to the paste supply area | region on a mask from the syringe of the screen printing machine in one embodiment of this invention. The flowchart of the main routine which shows the execution procedure of the screen printing operation which the screen printer in one embodiment of this invention performs The flowchart of the subroutine which shows the execution procedure of the screen printing operation which the screen printer in one embodiment of this invention performs (A) (b) (c) The figure explaining operation | movement at the time of screen printing work execution of the screen printer in one embodiment of this invention. (A) (b) (c) The figure explaining operation | movement at the time of screen printing work execution of the screen printer in one embodiment of this invention. (A) (b) The figure explaining operation | movement at the time of screen printing work execution of the screen printer in one embodiment of this invention (A) (b) The figure explaining operation | movement at the time of screen printing work execution of the screen printer in one embodiment of this invention (A) (b) (c) The figure explaining operation | movement at the time of screen printing work execution of the screen printer in one embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. 1, 2, and 3, the screen printing machine 1 according to the present embodiment carries in the substrate 2 loaded from another device (not shown) located on the upstream side of the flow of the substrate 2. Is performed at the printing work execution position, and screen printing for transferring the paste Pt (see FIG. 3) such as solder paste or conductive paste onto the electrode 3 on the surface of the substrate 2 is carried out and carried out downstream. To do. Hereinafter, for convenience of explanation, the horizontal plane direction in which the substrate 2 is transported in the screen printing machine 1 is defined as the X-axis direction, the horizontal plane direction orthogonal to the X-axis direction is defined as the Y-axis direction, and the vertical direction is defined as the Z-axis. Further, the Y-axis direction is the front-rear direction of the screen printing machine 1 and the X-axis direction is the lateral (left-right) direction, and the operator OP (FIG. 1) performs the operation on the screen printing machine 1 in the front-rear direction (FIG. 1 is the front side of the screen printing machine 1, and the opposite side (the upper side of the page in FIG. 1) is the rear side.

  1, 2, and 3, the screen printing machine 1 includes a substrate holding / moving unit 12 that is a substrate holding / moving unit provided on a base 11 and a metal provided above the substrate holding / moving unit 12. A plate-like mask 13 made of a thin plate material and having a large number (a plurality of) openings 13a (pattern holes) according to the arrangement of the electrodes 3 of the substrate 2, a pair of front and rear squeegees provided extending in the X-axis direction 14, a syringe 16 that is provided so as to be movable in the extending direction of the camera unit 15 and the squeegee 14 (X-axis direction) and that discharges the paste Pt when supplied with air pressure.

  2 and 3, the substrate holding / moving unit 12 includes a horizontal moving unit 21, a lifting / lowering unit 22, a conveyor unit 23, and a substrate holding unit 24.

  2 and 3, the horizontal moving unit 21 moves to the Y table 21a that moves in the Y-axis direction with respect to the base 11 by the operation of the Y table drive motor My, and to the Y table 21a by the operation of the X table drive motor Mx. The X table 21b that moves in the X axis direction, the θ table 21c that rotates around the Z axis with respect to the X table 21b, the base table 21d that is fixed to the upper surface of the θ table 21c, and the upper surface of the base table 21d that extends upward It consists of a plurality of lift table guides 21e provided.

  2 and 3, the elevating unit 22 is provided to extend upward from the upper surface of the elevating table 22a and the elevating table 22a which are guided by a plurality of elevating table guides 21e of the horizontal moving unit 21 and elevate with respect to the base table 21d. And a plurality of support unit lifting guides 22b.

  2 and 3, the conveyor unit 23 is attached to the upper end of the lower support unit elevating guide 22b, and a pair of front and rear belt conveyor supporting members 23a that elevate with respect to the base table 21d together with the elevating table 22a, and each belt conveyor supporting member. A pair of front and rear belt conveyors 23b supported by 23a is provided, and the front and rear belt conveyors 23b are operated in synchronization to carry the substrate 2 in the X-axis direction.

  2 and 3, the substrate holding unit 24 is a pair of front and rear provided movably in the Y-axis direction on the upper part of the receiving unit 25 provided below the conveyor unit 23 and the front and rear belt conveyor support members 23 a. The clamp member 26 (see also FIG. 1).

  2 and 3, the lower receiving unit 25 is guided by the lower receiving unit elevating guide 22b and can be moved up and down, and is lifted with respect to the elevating table 22a of the horizontal moving unit 21, thereby extending a plurality of lower extending units. The upper end of the receiving pin 25a is brought into contact with the lower surface of the substrate 2 supported at both ends by the front and rear belt conveyors 23b from below to support the substrate 2.

  2 and 3, the front and rear clamping members 26 are moved in opposite directions (that is, opened and closed in the Y-axis direction) via an opening / closing mechanism (not shown), so that both ends are moved by the front and rear belt conveyors 23b. The both sides (both end faces) in the Y-axis direction of the substrate 2 on which the portion is supported are clamped by sandwiching them from the outside of the substrate 2.

  As will be described later, the substrate holding and moving unit 12 raises the substrate 2 in a state where the substrate 2 is clamped by a pair of clamp members 26 so that the electrode 3 on the substrate 2 and the opening 13a of the mask 13 match. It functions as a substrate holding and moving means for bringing the upper surface of the substrate 2 into contact with the lower surface of the mask 13.

  In FIG. 1 and FIG. 2, a substrate carry-in conveyor 27 comprising a pair of front and rear belt conveyors 27 a is provided on the upstream side of the conveyor unit 23 constituting the substrate holding and moving unit 12, and on the downstream side of the conveyor unit 23 A substrate carry-out conveyor 28 comprising a pair of belt conveyors 28a is provided. The substrate carry-in conveyor 27 carries in the substrate 2 input from the outside (upstream side) of the screen printing machine 1 and delivers it to the conveyor unit 23 of the substrate holding / moving unit 12. The substrate 2 delivered from the conveyor unit 23 is carried out of the screen printer 1. As described above, the substrate carry-in conveyor 27, the conveyor unit 23 of the substrate holding and moving unit 12, and the substrate carry-out conveyor 28 function as a substrate carrying path 29 (FIG. 1) for carrying the substrate 2.

  In FIG. 1 and FIG. 2, a pair of gate-type frames 31 are provided on the base 11 so as to straddle the substrate carry-in conveyor 27 and the substrate carry-out conveyor 28 in the Y-axis direction. The holder 32 is supported.

  2, 3, and 4, the mask holder 32 includes a pair of front and rear guide members 33 that are attached to the gate-type frame 31 and extend in the X-axis direction above the substrate holding and moving unit 12. It consists of a pair of left and right mask support rails 34 extending in the Y-axis direction on a pair of guide members 33. The left and right ends of the mask 13 are supported by a pair of left and right mask support rails 34 provided in the mask holder 32 and held in a horizontal position above the substrate holding and moving unit 12.

  1 and 4, the mask 13 is supported by a mask frame 13w made of a rectangular frame-like member in plan view, and the rectangular region surrounded by the mask frame 13w has a large number of openings described above. 13a is provided.

  In FIG. 1, two sets of substrate side alignment marks mk are provided at diagonal positions of the substrate 2. On the other hand, in FIG. 4, the mask 13 is provided with a pair of mask side alignment marks MK arranged in correspondence with the substrate side alignment marks mk. When the substrate 2 is brought into contact with the mask 13 in a state where the substrate side alignment mark mk and the mask side alignment mark MK are coincident in plan view, the electrode 3 of the substrate 2 and the opening 13a of the mask 13 are matched. It becomes a state.

  2 and 3, the pair of portal frames 31 support both ends of an X-axis stage 35 extending in the X-axis direction so as to be slidable in the Y-axis direction. A camera support stage 36 is provided on the X-axis stage 35 so as to be movable in the X-axis direction. The camera unit 15 is attached to the camera support stage 36. The camera unit 15 includes a first camera 15a whose imaging field is directed downward and a second camera 15b whose imaging field is directed upward.

  1 and 2, both ends of a squeegee base 37 extending in the X-axis direction are supported by a pair of portal frames 31, and the squeegee base 37 is located above the mask 13 along the portal frame 31. It can freely reciprocate in the horizontal plane direction (Y-axis direction).

  2 and 3, two squeegee raising / lowering cylinders 38 are provided at positions facing the Y-axis direction at the center of the upper surface of the squeegee base 37. From these two squeegee raising / lowering cylinders 38, a squeegee raising / lowering shaft 38a comprising a piston rod extends through the squeegee base 37 in the vertical direction.

  2 and 3, a squeegee holder 39 extending in the X-axis direction is attached to the lower end of the squeegee lifting shaft 38a provided in each squeegee lifting cylinder 38, and the squeegee 14 described above is held in each squeegee holder 39. ing. Each squeegee 14 is formed of a “spar” -like member extending in the X-axis direction along the squeegee holder 39.

  When the squeegee lifting shaft 38a protrudes and retracts downward by each squeegee lifting cylinder 38, the squeegee 14 attached to the lower end of the squeegee lifting shaft 38a via the squeegee holder 39 moves up and down with respect to the squeegee base 37. Here, since the vertical distance between the mask 13 and the squeegee base 37 does not change, the squeegee 14 moves up and down with respect to the mask 13.

  Thus, the syringe 16 extends in a horizontal plane direction (X-axis direction) orthogonal to the Y-axis direction, which is the moving direction of the squeegee base 37, and is configured to be lifted and lowered below the squeegee base 37.

  As shown in FIGS. 5 and 6, the syringe 16 is attached to the front portion of the squeegee base 37 (left side in FIG. 6) via a syringe mounting bracket 41, and the syringe mounting bracket 41 faces the squeegee base 37. The slider 42 provided on the rear surface engages with a slide guide 43 provided with the front surface of the squeegee base 37 extending along the X axis so as to be movable in the direction in which the squeegee 14 extends (X axis direction).

  5 and 7, a pair of brackets (a motor mounting bracket 44 and a driven pulley mounting bracket 45) are attached to both ends in the X-axis direction of the upper end of the upper surface of the squeegee base 37. A syringe moving motor 46 is attached. A drive shaft 46a (FIG. 6) of the syringe movement motor 46 extends horizontally through the motor mounting bracket 44, and a drive pulley 47 is attached to the tip thereof. On the other hand, a driven pulley 48 is attached to a pulley shaft (not shown) that extends horizontally forward from the driven pulley mounting bracket 45.

  5 and 7, a toothed belt 49 is stretched around the drive pulley 47 and the driven pulley 48, and the upper surface of the upper portion of the syringe mounting bracket 41 is fixed to the lower surface of the toothed belt 49. For this reason, when the drive shaft 46a of the syringe movement motor 46 is driven and the drive pulley 47 rotates, the toothed belt 49 meshed with the drive pulley 47 and the driven pulley 48 travels in the X-axis direction, and accordingly, the syringe mounting bracket 41 (therefore, the syringe 16), the region in front of the squeegee base 37 is in the horizontal plane direction (X-axis direction) orthogonal to the direction in which the squeegee base 37 reciprocates (Y-axis direction) with respect to the squeegee base 37. Moving.

  In FIG. 6, the syringe 16 is provided on the front surface of the syringe mounting bracket 41 provided in front of the squeegee base 37 along an axis J extending downward and inclined backward by an angle φ with respect to the vertical line VL. ing. The syringe 16 has a nozzle portion 16a having a paste supply port 16p at its lower end that is movable along the axis J, and moves the nozzle portion 16a downward (that is, the paste supply port 16p) to move the front squeegee 14 forward. The overhanging position (see the nozzle portion 16a indicated by the alternate long and short dash line in FIG. 6) and the storage position where the paste supply port 16p at the lower end of the nozzle portion 16a is moved upward (the nozzle portion indicated by the solid line in FIG. 6) 16a)). Here, the angle φ is arbitrarily set as an angle at which the paste Pt can be supplied directly below the squeegee 14 in front in a state where the nozzle portion 16a of the syringe 16 is located at the overhang position.

  The syringe 16 discharges the built-in paste Pt when air pressure is supplied to the inside in a state where the nozzle portion 16a is extended to the protruding position. The movement range (movement stroke) of the syringe 16 in the X-axis direction can cover at least the dimension in the X-axis direction (direction in which the squeegee 14 extends) of the substrate 2 handled by the screen printing machine 1 (both ends of the substrate 2 are covered). Range).

  The operations of the substrate carry-in conveyor 27 as the substrate carrying path 29 for carrying the substrate 2, the conveyor unit 23 of the substrate holding and moving unit 12, and the substrate carry-out conveyor 28 are controlled by a control device 50 (FIG. 8) provided in the base 11. ) Is performed by controlling the operation of the substrate transport path operating mechanism 51 (FIG. 8) including an actuator (not shown).

  The raising / lowering operation of the lower receiving unit 25 included in the substrate holding unit 24 of the substrate holding / moving unit 12 is performed by the control device 50 controlling the operation of the lower receiving unit raising / lowering mechanism 52 (FIG. 8) including an actuator (not shown). . The opening / closing operation (clamping and releasing operation of the substrate 2) of the front and rear clamp members 26 provided in the substrate holding unit 24 of the substrate holding / moving unit 12 is performed by a clamp device opening / closing mechanism 53 (see FIG. This is done by performing the operation control of 8). The control device 50 raises the lower receiving unit 25 to bring the lower receiving pins 25a into contact with the lower surface of the substrate 2, and holds the substrate 2 by clamping it from both sides of the substrate 2 with the front and rear clamping members 26. .

  Movement of the camera unit 15 in the horizontal plane, that is, movement of the X-axis stage 35 in the Y-axis direction with respect to the pair of portal frames 31 and movement of the camera support stage 36 in the X-axis direction with respect to the X-axis stage 35 Each control is performed when the control device 50 controls the operation of the camera moving mechanism 54 (FIG. 8) including an actuator (not shown). Further, the first camera 15a and the second camera 15b constituting the camera unit 15 each perform an imaging operation under the control of the control device 50, and the acquired image data is input to the control device 50 (FIG. 8).

  The control device 50 operates the first camera 15a, the second camera 15b, and the camera moving mechanism 54, thereby imaging the substrate-side alignment mark mk by the first camera 15a and mask-side alignment by the second camera 15b. The mark MK is imaged, and the positions of the substrate 2 and the mask 13 are detected.

  The horizontal movement unit 21 provided in the substrate holding and moving unit 12 moves the substrate holding unit 24 in the horizontal plane. The control device 50 moves the Y table 21a in the Y-axis direction relative to the base 11, and moves the Y table 21a. The Y table drive motor My and the X table drive motor Mx described above that cause the X table 21b to move in the X axis direction and rotate the θ table 21c around the Z axis with respect to the X table 21b (that is, the base table 21d). This is done by controlling the operation of a horizontal movement mechanism 55 (FIG. 8) comprising a plurality of actuators and the like. The control device 50 operates the horizontal movement mechanism 55 based on the positions of the substrate 2 and the mask 13 detected by operating the camera unit 15, thereby causing the horizontal surface of the substrate 2 held by the substrate holding unit 24 to the mask 13. Align inward.

  The raising / lowering operation of the substrate holding part 24 by the raising / lowering part 22 included in the substrate holding / moving unit 12 is performed by the control device 50, which is a lifting mechanism 56 (not shown) or the like that causes the base table 21d of the lifting table 22a to move up and down. ). The control device 50 operates the elevating mechanism 56 to hold the substrate by the substrate holding unit 24, and aligns the mask 13 in the horizontal plane direction (and the upper surfaces of the front and rear clamp members 26). Is brought into contact with the lower surface of the mask 13 from below.

  The movement operation of the syringe 16 that moves the syringe 16 in the X-axis direction is performed when the control device 50 controls the operation of the syringe movement motor 46 described above, and the protrusion and subtraction operation (downward movement and upper movement) of the nozzle portion 16a of the syringe 16 is performed. The operation is performed by the control device 50 controlling the operation of the nozzle part projecting and retracting mechanism 57 (FIG. 8) including an actuator (not shown). In addition, the supply of air pressure to the syringe 16 and the stop operation thereof are performed by the control device 50 controlling the operation of the air pressure supply mechanism 58 (FIG. 8) including an actuator (not shown). The control device 50 supplies the paste Pt onto the mask 13 in contact with the substrate 2 by operating the syringe moving motor 46, the nozzle part projecting and retracting mechanism 57, and the air pressure supplying mechanism 58.

  The raising / lowering operation of each squeegee 14 with respect to the squeegee base 37 is performed by controlling the operation of the two squeegee raising / lowering cylinders 38 (see also FIG. 8) attached to the upper portion of the squeegee base 37. The operation control of the squeegee base 37 for reciprocating the front and rear squeegees 14 in the Y-axis direction is performed by the control device 50 controlling a squeegee base moving mechanism 59 (FIG. 8) including an actuator (not shown).

  The control device 50 operates the squeegee base moving mechanism 59 to position the squeegee base 37 above one of the front and rear clamp members 26 and then operates one of the two squeegee lifting cylinders 38 to operate the squeegee lifting cylinder. The squeegee 14 moved up and down by 38 is brought into contact with the upper surface of the clamp member 26 (the upper surface of the mask 13 with which the clamp member 26 is in contact) from above. Specifically, the front squeegee 14 is brought into contact with the upper surface of the front clamp member 26, and the rear squeegee 14 is brought into contact with the upper surface of the rear clamp member 26. Then, by operating the squeegee base moving mechanism 59 and moving the squeegee base 37 in the front-rear direction (Y-axis direction), the squeegee 14 is slid on the mask 13 and previously supplied onto the mask 13 by the syringe 16. The paste Pt is scraped by the squeegee 14 to transfer the paste Pt to the electrode 3 of the substrate 2 through the opening 13 a of the mask 13.

  The front squeegee 14 is slid from the front to the rear on the mask 13 between the upper surface of the front clamp member 26 and the upper surface of the rear clamp member 26. It is slid from the rear to the front on the mask 13 between the upper surface and the upper surface of the front clamp member 26. The transfer operation of the paste Pt by the front squeegee 14 and the transfer operation of the paste Pt by the rear squeegee 14 are executed alternately.

  9 (a) and 9 (b), a paste height detection sensor 60 is provided on the paste scraping surface (the surface facing forward in the rear squeegee 14) of the rear squeegee 14 (the squeegee 14 on the right side in FIG. 6). Is provided. The paste height detection sensor 60 is provided on one end side in the width direction (X-axis direction) of the rear squeegee 14, and projects a projector 60 a that projects the inspection light L in the X-axis direction, and the width of the rear squeegee 14. The light receiving device 60b is provided on the other end side in the direction and receives the inspection light L projected by the light projecting device 60a.

  While the control device 50 operates the squeegee base moving mechanism 59 and squeezes the paste Pt on the mask 13 to the front of the mask 13 by the rear squeegee 14, the light projector 60a of the paste height detection sensor 60 projects light. When the light receiver 60b does not receive the light L, the height h (FIG. 9B) of the paste Pt is a predetermined height corresponding to the height of the inspection light L measured from the upper surface of the mask 13. It is below H (FIG. 9 (b)).

  In the paste height storage unit 61 (FIG. 8) connected to the control device 50, information on whether or not the height h of the paste Pt on the mask 13 detected by the paste height detection sensor 60 is below a predetermined height H. Is memorized. The control device 50 performs the transfer operation of the paste Pt by the rear squeegee 14, and the height h of the paste Pt on the mask 13 is changed every time the paste height detection sensor 60 detects the height h of the paste Pt. It is determined whether or not the height is below the predetermined height H, and the determination result is written in the paste height storage unit 61 and updated. For this reason, the paste height storage unit 61 stores the latest information as to whether or not the height h of the paste Pt on the mask 13 is below the predetermined height H. At the start of mounting board production, the paste height storage unit 61 stores information indicating that the paste height h is lower than the predetermined height H.

  A reciprocating region R (FIGS. 7 and 10) is defined within a range in which the syringe 16 can be moved along the slide guide 43 in the X-axis direction by driving the syringe moving motor 46. This reciprocating movement area R is a printing operation for a substrate 2 having a maximum dimension in the X-axis direction (hereinafter referred to as “maximum dimension substrate 2”) among the substrates 2 that are in contact with the mask 13 by the substrate holding / moving unit 12. When positioned at the execution position, the center of the substrate 2 that includes both ends of the substrate 2 in the X-axis direction (the direction in which the squeegee 14 extends) and the center position of the reciprocating movement region R is positioned at the printing operation execution position. It is determined so as to coincide with the position in the X-axis direction.

  When supplying the paste Pt onto the mask 13, the control device 50 supplies air pressure to the syringe 16 and discharges the paste Pt from the syringe 16 while reciprocating the syringe 16 in the X-axis direction in the reciprocating region R. As a result, the paste Pt is supplied into the paste supply area Q (FIGS. 7 and 10) determined for each type of the substrate 2 as an area where the paste Pt on the mask 13 is to be supplied.

  Thus, the syringe 16 is movably provided in the reciprocating movement region R set to include both ends of the substrate 2 in contact with the mask 13 by the substrate holding and moving unit 12 in the extending direction (X-axis direction) of the squeegee 14. In response to the supply of air pressure, the paste Pt is discharged into the paste supply region Q on the mask 13.

  In FIG. 7, a first limit switch LS <b> 1 and a second limit switch LS <b> 2 are provided at the positions of both ends of the reciprocating region R at the front of the squeegee base 37. The first limit switch LS1 and the second limit switch LS2 are turned on when an operation piece (not shown) is operated by a part of the syringe 16, and outputs a detection signal of the syringe 16 to the control device 50 (FIG. 8).

  Here, the first limit switch LS1 is provided at a “reference position P1” that is a position corresponding to an end portion on one side (here, left side) of the reciprocating movement region R, and the second limit switch LS1. LS2 is provided at a “folding position P2” that is a position corresponding to an end of the position on the other side of the reciprocating region R (here, the right side) (FIG. 7). For this reason, when the syringe 16 is located at the reference position P1 of the reciprocating region R, the first limit switch LS1 is turned on, and the detection signal of the syringe 16 is output to the control device 50 (the second limit switch LS2 is turned off). ), When the syringe 16 is located at the folding position P2 of the reciprocating region R, the second limit switch LS2 is turned on and the detection signal of the syringe 16 is output to the control device 50 (the first limit switch LS1 is off). .

  The control device 50 starts the syringe 16 from the reference position P1 of the reciprocating movement region R toward the turn-back position P2, and then the syringe 16 is located on both sides of the paste supply region Q in the X-axis direction on the reference position P1 side. The supply of air pressure to the syringe 16 is started when reaching the forward air pressure supply start position Q1 (FIGS. 7 and 10) that is the end portion and is separated from the reference position P1 by the distance W1. The supply of the air pressure to the syringe 16 is stopped when reaching the forward air pressure supply stop position Q2 (FIG. 10), which is a position away from the forward air pressure supply start position Q1 by the predetermined distance W2 toward the folding position P2.

  Further, the control device 50 starts the syringe 16 from the folding position P2 of the reciprocating movement region R toward the reference position P1, and then the syringe 16 folds out of the positions of both ends of the paste supply region Q in the X-axis direction. Supply of air pressure to the syringe 16 is started when it reaches an inward air pressure supply start position Q3 (FIGS. 7 and 10) that is an end on the position P2 side and is separated from the turn-back position P2 by a distance W1. When the syringe 16 reaches the return side air pressure supply stop position Q4 (FIG. 10), which is a position separated from the return side air pressure supply start position Q3 by the predetermined distance W2 toward the reference position P1, the air pressure is supplied to the syringe 16. Stop.

  In the forward movement of the reciprocating movement region R of the syringe 16, the control device 50 confirms that the syringe 16 has reached the forward air pressure supply start position Q1 after the syringe 16 has started from the reference position P1 toward the folding position P2. Judgment is made based on the elapsed time from when the syringe 16 leaves the reference position P1. Specifically, the control device 50 measures the elapsed time from when the first limit switch LS1 is switched from on to off by the syringe 16 starting from the reference position P1, by the timer 62 (FIG. 8), The elapsed time measured by the timer 62 is a moving speed (v) determined by the number of rotations of the syringe moving motor 46 with respect to the distance W1 (FIG. 10) between the reference position P1 and the forward air pressure supply start position Q1. When it is detected that the time required for traveling (predetermined time T1) has been reached, it is determined that the syringe 16 has reached the forward air pressure supply start position Q1.

  Further, in the forward movement of the reciprocating movement region R of the syringe 16, the control device 50 indicates that the syringe 16 has reached the forward air pressure supply stop position Q <b> 2 after passing the forward air pressure supply start position Q <b> 1. Judgment is made based on the elapsed time from when the air pressure supply start position Q1 is reached. Specifically, the control device 50 determines the forward air pressure supply start position Q1 after the syringe 16 leaves the reference position P1 from the elapsed time from when the syringe 16 leaves the reference position P1 measured by the timer 62. The time obtained by subtracting the time required to reach (i.e., the predetermined time T1) is the time required to advance the distance W2 between the forward air pressure supply start position Q1 and the forward air pressure supply stop position Q2 ( When it is detected that the predetermined time T2) has been reached, it is determined that the syringe 16 has reached the forward air pressure supply stop position Q2.

  Further, the control device 50 determines that the syringe 16 has reached the return air pressure supply start position Q3 after the syringe 16 has departed from the return position P2 toward the reference position P1 in the return movement of the reciprocating movement region R of the syringe 16. Is determined by the elapsed time from when the syringe 16 departs from the folding position P2. Specifically, the control device 50 measures the elapsed time from when the second limit switch LS <b> 2 is switched from on to off by the syringe 16 starting from the folding position P <b> 2, and measures by the timer 62. That the elapsed time has reached the time (predetermined time T1) required to travel the distance W1 (FIG. 10) between the return position P2 and the return air pressure supply start position Q3 at the moving speed (v). When detected, it is determined that the syringe 16 has reached the return air pressure supply start position Q3.

  Further, the control device 50 indicates that the syringe 16 has reached the return side air pressure supply stop position Q4 after the syringe 16 has passed the return side air pressure supply start position Q3 in the return path movement of the reciprocation region R of the syringe 16. Judgment is made based on the elapsed time from when the return air pressure supply start position Q3 is reached. Specifically, the control device 50 starts the return air pressure supply start position Q3 after the syringe 16 leaves the turn-back position P2 from the elapsed time from when the syringe 16 leaves the turn-back position P2 measured by the timer 62. The time obtained by subtracting the time required to reach (that is, the predetermined time T1) is the time required to travel the distance W2 between the return-side air pressure supply start position Q3 and the return-side air pressure supply stop position Q4 ( When it is detected that the predetermined time T2) has been reached, it is determined that the syringe 16 has reached the return air pressure supply stop position Q4.

  The time data composed of the predetermined time T1 and the predetermined time T2 is determined for each type of the substrate 2 and stored in the time data storage unit 63 (FIG. 8) of the control device 50. Here, the data of the predetermined times T1 and T2 are determined for each type of the substrate 2 because the size of the paste supply region Q varies depending on the size of the substrate 2 to be screen-printed in the X-axis direction, Therefore, the timing of starting and stopping the supply of air pressure to the syringe 16 differs depending on the substrate 2.

  The time data can be obtained by the operator OP by directly inputting the time data from the input / output device 64 (FIG. 8) such as a touch panel connected to the control device 50, and the substrate 2 can be obtained from the substrate transport path 29. When it is configured to read the information on the substrate 2 from a barcode provided on the substrate 2 by a barcode reader (not shown) when it is carried in by the carry-in conveyor 27, it is obtained from the information read at that time. Also good.

  When the control device 50 determines that the syringe 16 has reached the forward air pressure supply start position Q <b> 1 based on the elapsed time measured by the timer 62 after the first limit switch LS <b> 1 is switched from on to off, the control device 50 returns to the syringe 16. The supply of air pressure to the syringe 16 is stopped when it is determined that the syringe 16 has reached the forward air pressure supply stop position Q2. For this reason, in the paste supply region Q on the mask 13, when the reciprocating region R is moved forward by the syringe 16, it is discharged from the syringe 16 from the forward air pressure supply start position Q1 to the forward air pressure supply stop position Q2. The paste Pt and the paste Pt that continues to come out of the syringe 16 until the pressure in the syringe 16 returns to a low pressure due to the supply stop of the air pressure after the syringe 16 has passed the forward air pressure supply stop position Q2 are supplied. .

  When the control device 50 determines that the syringe 16 has reached the return air pressure supply start position Q3 based on the elapsed time measured by the timer 62 after the second limit switch LS2 is switched from on to off, the syringe When the supply of air pressure to the syringe 16 is started and it is determined that the syringe 16 has reached the return air pressure supply stop position Q4, the supply of air pressure to the syringe 16 is stopped. For this reason, in the paste supply region Q on the mask 13, when the reciprocating region R is moved back and forth by the syringe 16, it is discharged from the syringe 16 from the return side air pressure supply start position Q3 to the return side air pressure supply stop position Q4. The paste Pt and the paste Pt that continues to come out of the syringe 16 until the pressure in the syringe 16 returns to a low pressure due to the supply stop of the air pressure after the syringe 16 passes the return-side air pressure supply stop position Q4 are supplied. .

  Thus, the syringe 16 discharges the paste Pt into the paste supply region Q on the mask 13 and superimposes it twice in the forward and backward paths of the reciprocating region R.

  FIG. 11A shows the distribution along the X-axis direction (direction in which the paste supply region Q extends) of the amount of paste Pt supplied from the syringe 16 into the paste supply region Q when the syringe 16 moves forward. FIG. 11B shows a distribution along the X-axis direction of the paste Pt supplied from the syringe 16 to the paste supply region Q when the syringe 16 moves backward. FIG. 11C shows a distribution along the X-axis direction of the amount of paste Pt supplied to the paste supply region Q from the syringe 16 reciprocated in the reciprocating region R.

  As can be seen from FIGS. 11 (a), 11 (b), and 11 (c), the amount of the paste Pt is locally increased in the paste supply region Q on the mask 13 both when the syringe 16 moves forward and when it moves backward. There is no place to increase. Further, since the profile of the discharge operation in which the syringe 16 discharges the paste Pt in the forward path of the reciprocating movement region R and the profile of the discharge operation in which the paste Pt is discharged in the return path of the reciprocating movement region R are the same, the syringe 16 The distribution in the X-axis direction of the paste Pt supplied to the paste supply region Q by 16 is symmetric with respect to the center position CT of the paste supply region Q in the X-axis direction. Therefore, the paste Pt in the paste supply area Q is easily uniformed as a whole, and the paste supply body PB (FIG. 10) in which the supply amount is uniformized in the X-axis direction as a whole in the paste supply area Q on the mask 13. It is formed.

  Next, the execution procedure of the screen printing operation by the screen printer 1 will be described with reference to the flowcharts of FIGS. 12 and 13 and the explanatory diagrams of FIGS. Here, FIG. 12 is a flowchart of a main routine showing the flow of the screen printing process executed by the screen printer 1, and FIG. 13 is a flowchart of a subroutine of one process in the main routine.

  When the screen printing operation is performed, the control device 50 of the screen printing machine 1 first sends the substrate carry-in conveyor 27 and the conveyor unit 23 in conjunction with each other and is sent from another device installed on the upstream side of the screen printing machine 1. After the substrate 2 is carried into the screen printing machine 1, the substrate 2 is stopped at the printing work execution position on the conveyor unit 23 (FIG. 14 (a). The substrate carrying-in step of step ST1 shown in FIG. 12).

  When the substrate carrying-in process in step ST1 is completed, the control device 50 closes the front and rear clamping members 26 and clamps the substrate 2 on the conveyor unit 23 from the Y-axis direction (FIG. 14B). Arrow A1) shown. Then, the lower receiving unit 25 is raised while the lifting table 22a is positioned at the lowered position with respect to the base table 21d (arrow B1 shown in FIG. 14C).

  The control device 50 raises the lower receiving unit 25 to bring the lower receiving pin 25a of the lower receiving unit 25 into contact with the lower surface of the central portion of the substrate 2 from below to push the substrate 2 upward. Is moved upward from the front and rear belt conveyors 23b, and the substrate 2 is moved upward while sliding both end portions (both end surfaces) of the substrate 2 with respect to the front and rear clamp members 26. And when the height of the upper surface of the board | substrate 2 becomes the same height as the upper surface of the clamp member 26, the raise of the receiving unit 25 is stopped. As a result, the substrate 2 is held by the substrate holder 24 (FIG. 14C). The substrate holding step of step ST2 shown in FIG.

  When the substrate holding process in step ST2 is completed, the control device 50 controls the operation of the camera moving mechanism 54, moves the X-axis stage 35 in the Y-axis direction, and moves the camera support stage 36 in the X-axis direction. Thus, the first camera 15a is positioned immediately above the substrate-side alignment mark mk provided on the substrate 2. Then, the first camera 15a is caused to image the substrate side alignment mark mk to acquire the image data, and the position of the substrate 2 is detected (FIG. 15 (a). Substrate position of step ST3 shown in FIG. 12). Detection step). Further, the control device 50 positions the second camera 15b immediately below the mask side alignment mark MK provided on the mask 13, and causes the second camera 15b to capture the mask side alignment mark MK. Image data is acquired, and the position of the mask 13 is detected (FIG. 15B) (mask position detection step of step ST4 shown in FIG. 12).

  When the mask position detection step of step ST4 is completed, the control device 50 performs the operation control of the horizontal moving unit 21 provided in the substrate holding and moving unit 12 to move the substrate 2 held by the substrate holding unit 24 in the horizontal plane direction, The substrate 2 alignment mark mk and the mask side alignment mark MK are vertically opposed so as to align the substrate 2 with respect to the mask 13 in the horizontal plane (alignment step of step ST5 shown in FIG. 12). .

  When the alignment process in step ST5 is completed, the control device 50 raises the lifting table 22a with respect to the base table 21d (arrow C1 shown in FIG. 15C), whereby the upper surface of the substrate 2 (printed surface). ) And the upper surfaces of the clamp members 26 are brought into contact with the lower side of the mask 13 (FIG. 15C) (contacting step ST6 shown in FIG. 12). As a result, the electrode 3 of the substrate 2 and the opening 13a of the mask 13 are matched, and the substrate 2 is in a state where the transfer operation of the paste Pt by the squeegee 14 is performed.

  When the above contact process is completed, the control device 50 determines whether or not to slide with the front squeegee 14 (sliding squeegee determination process in step ST7 shown in FIG. 12). In this sliding squeegee judgment step, when it is judged that the control device 50 will slide by the front squeegee 14, the height of the paste Pt on the mask 13 currently stored in the paste height storage unit 61 is determined. Based on the information whether or not the height h is below a predetermined height H, it is determined whether or not the current amount of paste Pt on the mask 13 (hereinafter referred to as paste amount) is sufficient (see FIG. Step ST8 paste amount determination step shown in FIG.

  In this paste amount determination step, when the paste height storage unit 61 stores information indicating that the height h of the paste Pt is lower than the predetermined height H, the paste amount is not sufficient (insufficient). If the information indicating that the height h of the paste Pt currently stored in the paste height storage unit 61 is greater than or equal to the predetermined height H is stored, it is determined that the amount of paste is sufficient.

  When determining that the paste amount is not sufficient in the paste amount determining step, the control device 50 supplies the paste Pt onto the mask 13 by the syringe 16 (FIG. 16A) .Paste supply in step ST9 shown in FIG. Process).

  In the paste supply process of step ST9, as shown in the subroutine of FIG. 13, the control device 50 firstly stores time data (predetermined time) from the time data storage unit 63 according to the type of the substrate 2 currently performing screen printing. (Data of T1 and predetermined time T2) is acquired (time data acquisition step of step ST21 shown in FIG. 13).

  After acquiring the time data in step ST21, the control device 50 causes the nozzle portion 16a of the syringe 16 to protrude to the protruding position (nozzle portion extending step of step ST22 shown in FIG. 13). Then, it is determined whether or not the first limit switch LS1 is currently turned on (first limit switch determination step of step ST23 shown in FIG. 13). This is to check whether the syringe 16 is currently in a state of being positioned at the reference position P1 of the reciprocating movement region R. When it is detected that the first limit switch LS1 is not turned on, The control device 50 notifies the operator OP of an error via the input / output device 64 (error notification step of step ST24 shown in FIG. 13). On the other hand, when it is detected in step ST23 that the first limit switch LS1 is currently turned on, the control device 50 controls the operation of the syringe movement motor 46 and moves the syringe 16 to the folding position P2. Is started (syringe movement start step of step ST25 shown in FIG. 13).

  When the movement of the syringe 16 is started in step ST25, the control device 50 determines whether or not the first limit switch LS1 is turned off from on at intervals of a minute time (for example, several microseconds) (shown in FIG. 13). First limit switch determination step in step ST26). When it is determined that the first limit switch LS1 has been turned off from on, the control device 50 uses the timer 62 to start measuring the elapsed time since it was determined that the first limit switch LS1 has been turned off (FIG. (Elapsed time measurement start step of step ST27 shown in FIG. 13).

  After starting the measurement of the elapsed time in step ST27, the control device 50 determines whether or not the predetermined time T1 has elapsed from the start of the measurement of the elapsed time at a minute time interval (whether the elapsed time has reached the predetermined time T1). Determination is performed (time elapse determination step of step ST28 shown in FIG. 13).

  When the controller 50 determines in step ST28 that the predetermined time T1 has elapsed from the start of measurement of the elapsed time, and detects that the syringe 16 has reached the forward air pressure supply start position Q1, the controller 50 supplies the air pressure to the syringe 16. Start (air pressure supply start step of step ST29 shown in FIG. 13). Thereby, discharge of the paste Pt by the syringe 16 is started.

  When starting the supply of air pressure to the syringe 16 at step ST29, the control device 50 starts measuring the elapsed time from when the supply of air pressure to the syringe 16 is started by the timer 62 (step ST30 shown in FIG. 13). Elapse time measurement start process).

  When starting the measurement of the elapsed time in step ST30, the control device 50 determines whether or not the predetermined time T2 has elapsed from the start of the measurement of the elapsed time at a minute time interval (whether the elapsed time has reached the predetermined time T2). (Time elapse determination step of step ST31 shown in FIG. 13).

  If it is determined in step ST31 that the predetermined time T2 has elapsed from the start of measurement of the elapsed time, the control device 50 stops the supply of air pressure to the syringe 16 (air pressure supply stop process in step ST32 shown in FIG. 13). Thereby, the discharge of the paste Pt from the syringe 16 is completed, but the paste Pt continues to be discharged from the syringe 16.

  When the supply of air pressure to the syringe 16 is stopped in step ST32, the control device 50 determines whether or not the second limit switch LS2 is turned on from the OFF state at a minute time interval (the first step ST33 shown in FIG. 13). 2 limit switch determination step). Then, the control device 50 determines that the second limit switch LS2 has been turned on from off, and stops the movement of the syringe 16 when detecting that the syringe 16 has reached the folding position P2 of the reciprocating movement region R (see FIG. Syringe movement stop step of step ST34 shown in FIG. 13).

  After stopping the movement of the syringe 16 in step ST34, the control device 50 starts the movement of the syringe 16 in the opposite direction, that is, from the folding position P2 toward the reference position P1 (see FIG. Syringe movement start process of step ST35 shown in FIG. 13).

  When the movement of the syringe 16 is started in step ST35, the control device 50 determines whether or not the second limit switch LS2 has been turned off from the on state at a minute time interval (the second limit of step ST36 shown in FIG. 13). Switch determination step). When the control device 50 determines that the second limit switch LS2 is turned off from on, the control device 50 starts measuring the elapsed time from the time when the timer 62 determines that the second limit switch LS2 is turned off (FIG. Step ST37 elapsed time measurement start step shown in FIG.

  After starting the elapsed time measurement in step ST37, the control device 50 determines whether or not the predetermined time T1 has elapsed from the start of the elapsed time measurement at a minute time interval (whether the elapsed time has reached the predetermined time T1). Determination is performed (time elapse determination step of step ST38 shown in FIG. 13).

  When the control device 50 determines in step ST38 that the predetermined time T1 has elapsed from the start of measurement of the elapsed time and detects that the syringe 16 has reached the return-side air pressure supply start position Q3, the controller 50 supplies air pressure to the syringe 16. Start (air pressure supply start step of step ST39 shown in FIG. 13). Thereby, discharge of the paste Pt by the syringe 16 is started.

  When starting the supply of air pressure to the syringe 16 in step ST39, the control device 50 starts measuring the elapsed time from when the supply of air pressure to the syringe 16 is started by the timer 62 (step ST40 shown in FIG. 13). Elapse time measurement start process).

  When starting the measurement of the elapsed time in step ST40, the control device 50 determines whether or not the predetermined time T2 has elapsed from the start of the measurement of the elapsed time at a minute time interval (whether the elapsed time has reached the predetermined time T2). (Time elapse determination step of step ST41 shown in FIG. 13)

  If it determines with predetermined time T2 having passed since the measurement start of elapsed time by step ST41, the control apparatus 50 will stop supply of the air pressure to the syringe 16 (air pressure supply stop process of step ST42 shown in FIG. 13). Thereby, the discharge of the paste Pt from the syringe 16 is completed, but the paste Pt continues to be discharged from the syringe 16.

  When the supply of air pressure to the syringe 16 is stopped in step ST42, the control device 50 determines whether or not the first limit switch LS1 has been turned on from off (step ST43 in FIG. 13 shown in FIG. 13). 1 limit switch determination step). Then, the control device 50 determines that the first limit switch LS1 has been turned on from off, and stops the movement of the syringe 16 when detecting that the syringe 16 has reached the reference position P1 of the reciprocating movement region R (FIG. Syringe movement stop step of step ST44 shown in FIG. 13). Thereby, in the paste supply region Q on the mask 13, the paste supply body PB in which the supply amount is uniformed as a whole in the X-axis direction is formed.

  When the movement of the syringe 16 is stopped in step ST44, the control device 50 stores the nozzle portion 16a of the syringe 16 (nozzle portion storing step in step ST45 shown in FIG. 13). Thereby, the paste supply process by the syringe 16 is completed, and the amount of paste that has been insufficient is recovered. After storing the nozzle portion 16a of the syringe 16 in step ST45, the control device 50 returns to the main routine.

  When the control device 50 finishes executing the paste supply process in step ST9, when it is determined in step ST7 that sliding is to be performed by the rear squeegee 14 or when it is determined in step ST8 that the paste amount is sufficient. Then, one of the front and rear squeegees 14 is lowered, and the lower end of the squeegee 14 is brought into contact with the portion of the mask 13 in contact with the clamp member 26 (one of the two clamp members 26) from above (from above). Fig. 16 (b) is a squeegee contact step of step ST10 shown in Fig. 12).

  When the squeegee 14 is in contact with the mask 13 at this time, when the squeegee base 37 is positioned above the front clamp member 26 (FIG. 16A), the front squeegee 14 (FIGS. 16A and 16B). When the squeegee base 37 is positioned above the rear clamp member 26, the rear squeegee 14 (the right squeegee 14 in FIGS. 16A and 16B) To do.

  The control device 50 moves the squeegee base 37 when the squeegee 14 is brought into contact with the upper surface of the mask 13. Here, if the squeegee 14 in contact with the mask 13 is the front squeegee 14, the squeegee base 37 is moved rearward (arrow D1 shown in FIG. 17A), and the squeegee 14 is in contact with the mask 13. If is the rear squeegee 14, the squeegee base 37 is moved forward (arrow D2 shown in FIG. 17B).

  As a result, the squeegee 14 moves (slids) relative to the mask 13, and the paste Pt on the mask 13 is scraped by the paste scraping surface of the squeegee 14 and pushed into the opening 13 a of the mask 13. The paste Pt is transferred onto the second electrode 3 (paste transfer step of step ST11 shown in FIG. 12).

  When the paste Pt has been scraped in front of the mask 13 by the rear squeegee 14 in the paste transfer step of step ST11, the control device 50 performs the rear squeegee 14 based on the detection information from the paste height detection sensor 60. It is determined whether the height h of the paste Pt in front of is lower than the predetermined height H, and the result is written in the paste height storage unit 61 (stored in the paste height storage unit 61), Next, it is used at the time of step ST8 performed on the substrate 2 on which screen printing is performed.

  When the paste transfer process in step ST11 is completed, the control device 50 raises the squeegee 14 to separate the squeegee 14 from the mask 13 (squeegee separation process in step ST12 shown in FIG. 12).

  When the squeegee separation step of step ST12 is completed, the control device 50 lowers the lifting table 22a with respect to the base table 21d (arrow C2 shown in FIG. 18A) to separate the substrate 2 from the mask 13 (FIG. 18 (a)). Thus, the plate separation is performed (the plate separation step of step ST13 shown in FIG. 12).

  When the plate separating process of step ST13 is completed, the control device 50 operates the clamp member 26 to release the clamp of the substrate 2 (arrow A2 shown in FIG. 18B), and then raises and lowers the lower receiving unit 25. The table 22a is lowered (arrow B2 shown in FIG. 18C). Thereby, the board | substrate 2 is dropped on the conveyor part 23, and holding | maintenance of the board | substrate 2 by the board | substrate holding | maintenance part 24 is cancelled | released (FIG.18 (c). Substrate holding | maintenance cancellation | release process of step ST14 shown in FIG. 12).

  When the substrate holding release process of step ST14 is completed, the control device 50 operates the horizontal moving unit 21 included in the substrate holding and moving unit 12 to adjust the position of the conveyor unit 23 with respect to the substrate carry-out conveyor 28, and then the conveyor unit 23 and the substrate carry-out conveyor 28 are operated in an interlocked manner, the substrate 2 on the conveyor unit 23 is transferred to the substrate carry-out conveyor 28, and the substrate 2 is directly carried out of the screen printing machine 1 (the substrate carry-out process of step ST15 shown in FIG. 12). ).

  When the substrate carry-out process in step ST15 is completed, the control device 50 determines whether there is another substrate 2 to be screen-printed (substrate presence determination process in step ST16 shown in FIG. 12). As a result, if there is another substrate 2 to be screen-printed, the process returns to step ST1 to carry in a new substrate 2, and if there is no other substrate 2 to be screen-printed, a series of screen printing operations. Exit.

  The substrate 2 carried out from the screen printing machine 1 is delivered to another component mounting apparatus (not shown) such as a component mounting machine located on the downstream side of the screen printing machine 1.

  As described above, the screen printing machine 1 according to the present embodiment supplies air pressure to the syringe 16 while reciprocating the syringe 16 in the reciprocating movement region R, so that each of the forward path and the returning path of the reciprocating movement region R is provided. The squeegee 14 is lowered with respect to the squeegee base 37 and the control device 50 as the syringe operation control means for supplying the paste Pt to the paste supply area Q set on the mask 13, and the paste Pt is supplied by the syringe 16. The squeegee lifting cylinder 38 as squeegee lowering means for abutting the squeegee 14 on the mask 13 and the squeegee base 37 moved in the horizontal plane direction (Y-axis direction) with the squeegee 14 abutting on the mask 13. A ski as a squeegee base moving means for sliding the squeegee 14 on the mask 13. The control device 50 includes a dibase moving mechanism 59, and the control device 50 is configured so that the syringe 16 is connected to one end side of the paste supply region Q (the outward air pressure supply start position Q1 and the return route) in each of the forward path and the return path of the syringe 16 in the reciprocating movement area R When reaching the side air pressure supply start position Q3), the supply of air pressure to the syringe 16 is started, and the syringe 16 is connected to the other end side of the paste supply area Q (the forward side air pressure supply stop position Q2 and the return side air pressure supply stop position Q4). The supply of air pressure to the syringe 16 is stopped before reaching ().

  The screen printing method in the present embodiment is a screen printing method by the screen printer 1 in the present embodiment, and by supplying air pressure to the syringe 16 while reciprocating the syringe 16 in the reciprocating movement region R. In each of the forward path and the backward path of the reciprocating movement area R, the process of supplying the paste Pt to the paste supply area Q set on the mask 13 (paste supply process of step ST9), and the squeegee 14 to the squeegee base 37 A step of lowering and bringing the squeegee 14 into contact with the mask 13 to which the paste Pt has been supplied by the syringe 16 (step S10), and a squeegee base 37 with the squeegee 14 in contact with the mask 13 Is moved in the horizontal plane direction (Y-axis direction), and the squeegee 14 is 13, including the step of sliding on step 13 (paste transfer step of step ST11), and the step of supplying the paste Pt to the paste supply region Q by the syringe 16 (paste supply step of step ST9), the reciprocating region of the syringe 16 In each of the forward path and the backward path of movement in R, when the syringe 16 reaches one end side of the paste supply area Q (the forward path air pressure supply start position Q1 and the return path air pressure supply start position Q3), the air pressure to the syringe 16 is reduced. The supply is started, and the supply of air pressure to the syringe 16 is stopped before the syringe 16 reaches the other end side of the paste supply region Q (the outward side air pressure supply stop position Q2 and the return side air pressure supply stop position Q4). ing.

  In the screen printing machine 1 and the screen printing method in the present embodiment, the syringe 16 reaches the one end side of the paste supply area Q in each of the forward path and the return path of the movement of the syringe 16 in the reciprocating movement area R. The supply of air pressure to the syringe is started and the supply of air pressure to the syringe is stopped before the syringe 16 reaches the other end side of the paste supply region Q. From the one end side of the paste supply region Q, The paste Pt discharged from the syringe 16 is supplied up to the point where the supply of air pressure is stopped, but the portion between the point where the supply of air pressure is stopped and the other end side is supplied with air pressure to increase the pressure. Until the pressure inside the syringe 16 is returned to a low pressure (atmospheric pressure level) by stopping the supply of air pressure, the amount of paste Pt that continues to come out of the syringe is It is fed. For this reason, after the supply of air pressure to the syringe 16 is stopped, there is no inconvenience that the paste Pt that continues to be discharged from the syringe 16 is intensively supplied to a part of the paste supply region Q. Then, since the paste is supplied in each of the forward path and the backward path of the reciprocating movement region R of the syringe, the paste Pt in the paste supply area Q is based on the supply during the forward movement of the syringe 16 and the syringe 16. It is easy to make uniform as a whole by the supply during the return path movement, and it is possible to suppress the occurrence of printing defects due to the non-uniform supply of the paste Pt on the mask 13.

  Further, in the present embodiment, the control device 50 that is the syringe operation control means determines the timing for stopping the supply of air pressure to the syringe 16 based on the elapsed time from the start of supply of air pressure to the syringe 16. Since there is no need to detect the position of the syringe 16 with respect to the mask 13, the paste Pt supply system can be configured at low cost. However, the method of determining the timing for stopping the supply of air pressure to the syringe 16 based on the elapsed time from the start of supplying air pressure to the syringe 16 is an example, and the position of the syringe 16 with respect to the mask 13 is detected. Then, the timing may be determined.

  Provided are a screen printing machine and a screen printing method capable of suppressing the occurrence of printing defects due to non-uniform supply of paste on a mask.

1 Screen Printer 2 Substrate 3 Electrode 12 Substrate Holding / Moving Unit (Substrate Holding / Moving Unit)
13 Mask 13a Opening 14 Squeegee 16 Syringe 26 Clamp Member 37 Squeegee Base 38 Squeegee Lifting Cylinder (Squeegee Lowering Unit)
50 Control device (syringe operation control means)
59 Squeegee base moving mechanism (squeegee base moving means)
R reciprocating movement area Q paste supply area Pt paste

Claims (4)

A mask having a plurality of openings according to the arrangement of the electrodes on the substrate;
A substrate holding and moving means for raising the substrate in a state where the substrate is clamped by a pair of clamp members, and bringing the upper surface of the substrate into contact with the lower surface of the mask so that the electrode on the substrate matches the opening of the mask;
A squeegee base that is moved in the horizontal plane above the mask;
A squeegee that extends in a horizontal plane direction orthogonal to the moving direction of the squeegee base and is raised and lowered below the squeegee base;
A syringe that is movably provided in a reciprocating region set to include both ends of the substrate squeegee extending direction that is in contact with the mask by the substrate holding and moving means, and that discharges paste by receiving air pressure;
Syringe operation control means for supplying the paste to the paste supply area set on the mask in each of the forward path and the return path of the reciprocation area by supplying air pressure to the syringe while reciprocating the syringe in the reciprocation area;
Squeegee lowering means for lowering the squeegee with respect to the squeegee base and bringing the squeegee into contact with the mask supplied with the paste by a syringe;
Squeegee base moving means for sliding the squeegee on the mask by moving the squeegee base in a horizontal plane while the squeegee is in contact with the mask,
The syringe operation control means starts supplying air pressure to the syringe when the syringe reaches one end side of the paste supply area in each of the forward path and the return path of the movement in the reciprocating movement area of the syringe. A screen printing machine characterized in that the supply of air pressure to the syringe is stopped before reaching the other end of the screen.   The screen printing machine according to claim 1, wherein the syringe operation control means determines the timing of stopping the supply of air pressure to the syringe based on the elapsed time from the start of supplying air pressure to the syringe. A substrate having a plurality of openings according to the arrangement of electrodes on the substrate and a substrate clamped by a pair of clamp members, the substrate is raised, and the substrate on the substrate and the mask openings are aligned. The substrate holding and moving means for bringing the upper surface of the substrate into contact with the lower surface of the mask, the squeegee base moved in the horizontal plane above the mask, and extending in the horizontal plane perpendicular to the moving direction of the squeegee base, and moved up and down below the squeegee base And a reciprocating movement region set to include both ends of the squeegee extending in the direction in which the squeegee extends in contact with the mask by the substrate holding and moving means. A screen printing method by a screen printing machine equipped with a syringe to perform,
Supplying air pressure to the syringe while reciprocating the syringe in the reciprocating movement region, thereby supplying the paste to the paste supply region set on the mask in each of the forward path and the return path of the reciprocating movement area;
Lowering the squeegee with respect to the squeegee base and bringing the squeegee into contact with the mask supplied with the paste by a syringe;
Moving the squeegee base in a horizontal plane direction while the squeegee is in contact with the mask, and sliding the squeegee on the mask.
Supplying air pressure to the syringe when the syringe reaches one end side of the paste supply area in each of the forward path and the return path of the movement in the reciprocating movement area of the syringe during the process of supplying the paste to the paste supply area by the syringe The screen printing method is characterized in that supply of air pressure to the syringe is stopped before the syringe reaches the other end side of the paste supply region.   The timing for stopping the supply of air pressure to the syringe during execution of the step of supplying the paste to the paste supply region by the syringe is determined based on the elapsed time from the start of supplying the air pressure to the syringe. 4. The screen printing method according to 3.

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